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Variations in the time of onset of the breeding season in Clun ewes

Published online by Cambridge University Press:  27 March 2009

J. L. Lees
J. L. Lees
Affiliation:
Department of Agriculture (Animal Husbandry), University College of Wales, Aberystwyth
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Extract

Variations in the time of onset of the breeding season in Clun ewes have been studied during the four years 1962-65. Differences within seasons were studied in 1963 and 1964 by scattering the lambing over the first 7 months of the year. The date of first service then appears to be very highly dependent on the date of previous lambing. Time of previous weaning appears to be less important.

Very highly significant differences have been found between seasonal means and these differences have been shown to be significantly related to the mean ambient temperature during a limited period between mid-summer and the mean date for the resumption of cyclic activity in the ewes. The higher this temperature the later the onset of breeding activity. Over the years individual ewes have tended to breed consistently either early or late.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 67 , Issue 2 , October 1966 , pp. 173 - 179
Copyright
Copyright © Cambridge University Press 1966

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References

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